Tail wheel transporter

ABSTRACT

A tail wheel transporter with an off-center single-beam chassis in a tricycle carriage coupled to a towing arm. The single beam chassis pivotably supports a lifting foot member of a four bar mechanism that is side mounted on the single-beam chassis. The lifting foot supports two studs, one fixed and one adjustable, for engaging a tail wheel. The lifting arm is coupled to the four bar mechanism and is manually operated to lift the tail wheel off the ground. In the lifted position, the lifting arm is latched to the towing arm so that constant manual force to maintain lift is not required. The tail wheel is received on the studs between the front and rear axles and exerts force below the height of the rear axle, so no manual force is required to maintain balance during operation. A low-profile bifurcated front wheel allows use under low-hanging vehicle parts.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/169,680 filed Jun. 27, 2011 (issued as U.S. Pat. No.8,336,900) by the same inventor which, in turn, claims the benefit ofU.S. Provisional Patent Application 61/362,342 filed Jul. 8, 2010 by thesame inventor.

FIELD OF THE INVENTION

This invention relates to a device for moving an aircraft having tailwheel while the aircraft is on the ground. The invention further relatesto a lever jack on a dolly.

BACKGROUND

In general aviation, it is sometimes necessary to move aircraft on anaircraft hanger floor or on a tarmac without powering up the aircraftengine. For aircraft equipped with tail wheels (hereinafter “tail wheelaircraft”), it is generally preferred to move the aircraft by graspingthe tail and then pushing, pulling, and/or turning the aircraft.Depending on the weight and design of the tail wheel aircraft, this maybe a strenuous task. The tail of a tail wheel aircraft is the locationof several of the aircraft's control surfaces. Pushing or pulling ofthese control surfaces for the purpose of ground movement is generallynot recommended and could cause damage that could result in loss ofcontrol of the aircraft while in flight.

US Patent Application Publication Number 20060056949 A1 published 2006Mar. 16 on behalf of Eckert for a TRANSPORT VEHICLE FOR AIRCRAFTdiscloses a tricycle wheel arrangement on a bifurcated chassis thatreceives the aircraft wheel between the axles. The two drive wheels (ortracks) are independently driven for steering. As a motorized system,Eckert's invention is very heavy, very complex, and expensive.

U.S. Pat. No. 5,071,151 issued 1991 Dec. 10 to Irwin for a TAIL WHEELAIRCRAFT DOLLY discloses a two-wheeled dolly with two-arms, positionedon a handle, for receiving the tail wheel from the side. The long handlefrom the axle is used to lift and balance the tail of the aircraftduring movement. Constant manual force must be applied to the handle tomaintain lift and balance.

U.S. Pat. No. 1,902,834 issued on 1933 Mar. 28 to Cohen-Venezian for aTAIL-SUPPORTING TRUCK FOR AEROPLANES discloses the use of two wheels ona single axle with a cup or support for receiving a tail wheel above theaxle. An elongated handle coupled to the axle requires constant force tobe manually applied to maintain balance during operation.

U.S. Pat. No. 5,511,926 issued 1996 Apr. 30 to Iles for MOVEMENT OFAIRCRAFT discloses a two-axle bifurcated chassis on a self-propelleddolly. Two drive wheels are on opposite sides of the bifurcated chassisand a closely set pair of wheels is pivotably mounted to the chassis anddirected by manual operation of an elongated handle. The tail wheel tobe lifted is engaged between the bifurcated chassis members. Beingmotorized and battery powered, Iles' invention is heavy and expensive.

U.S. Pat. No. 6,636,709 B1 issued 2003 Mar. 25 to McVaugh for a SMALLAIRCRAFT POWER TUG discloses a two-wheel assembly with arms for engagingthe nose wheel axle and a drive wheel. The drive wheel is powered by apower drill through a drive train in the elongated handle. McVaugh doesnot lift the nose wheel, but can tilt the dolly to a tricycleconfiguration when not engaged with an aircraft for free wheeling.

U.S. Pat. No. 4,854,803 issued on 1989 Aug. 8 to Coccaro for anAPPARATUS AND METHOD FOR JACKING AND DOLLYING AN AFFIXED VEHICLE WHEELASSEMBLY discloses a four-castered U-shaped chassis with an elongatedhandle. The casters are attached on chassis members with dual-angledends. The U-shaped chassis engages a wheel from the side.

Therefore, a need exists for a tail wheel transporter that islightweight and does not require the application of constant manualforce to maintain lift or balance. A need also exists for a tail wheeltransporter that is easy to steer. A need also exists for a tail wheeltransporter that is adaptable to tail wheels of various widths. A needexists for a tail wheel transporter that can be manufactured in varioussizes and strengths for retaining tail wheels and aircraft of variousmasses. A need also exists for a tail wheel transporter that can beadapted to lift tail wheels of various diameters. A need also exists fora tail wheel transporter that is inexpensive to manufacture and ship. Aneed also exists for a tail wheel transporter that allows groundtransport of an aircraft without touching or damaging the controlsurfaces of the aircraft.

OBJECTS AND FEATURES OF THE INVENTION

A primary object and feature of the present invention is to overcome theabove-mentioned problems and fulfill the above-mentioned needs.

Another object and feature of the present invention is to provide a tailwheel transporter that is lightweight and does not require theapplication of constant manual force to maintain lift or balance.Another object and feature of the present invention is to provide a tailwheel transporter that is easy to steer. Another object and feature ofthe present invention is to provide a tail wheel transporter that isadaptable to tail wheels of various widths. Another object and featureof the present invention is to provide a a tail wheel transporter thatcan be manufactured in various sizes and strengths for retaining tailwheels and aircraft of various masses. Another object and feature of thepresent invention is to provide a tail wheel transporter that can beadapted to lift tail wheels of various diameters. Another object andfeature of the present invention is to provide a tail wheel transporterthat is inexpensive to manufacture and ship.

It is an additional primary object and feature of the present inventionto provide a tail wheel transporter that is safe, inexpensive, easy toclean, and handy. Another object and feature of the present invention isto provide a tail wheel transporter that allows ground transport of anaircraft without touching or damaging the control surfaces of theaircraft. Other objects and features of this invention will becomeapparent with reference to the following descriptions.

SUMMARY OF THE INVENTION

In accordance with a preferred embodiment hereof, the present inventionprovides a tail wheel transporter including: a tricycle carriage furtherincluding a main frame extending off-centered from a rear axle to afront caster attachment plate; a pivot bar pivotably mounted to a sideof the main frame proximate a centerline orthogonal to the rear axle; alifting foot pivotably coupled to the pivot bar and extendinghorizontally, when in a quiescent state, from the pivot bar to a pointbehind the front caster attachment plate, where the main frame, thepivot bar, and the lifting foot are three bars of a four bar mechanism;a lifting arm extending from the pivot bar; a towing arm extending fromthe main frame; and a latch operable to releasably couple the liftingarm to the towing arm when the lifting arm is in a lifted position. Thetail wheel transporter, further including a biasing mechanism operableto bias the lifting foot toward a non-lifted position. The tail wheeltransporter, further including a fourth bar of the four bar mechanismpivotably coupled on first and second ends to the main frame and thelifting foot, respectively. The tail wheel transporter, where thelifting foot further includes a first stud extending sideways from thelifting foot across the centerline. The tail wheel transporter, wherethe first stud further includes an axle for one pivotable coupling ofthe four bar mechanism. The tail wheel transporter, where the liftingfoot further includes a second stud extending sideways from the liftingfoot across the centerline and having an adjustable position on thelifting foot. The tail wheel transporter, where the adjustable positionincludes a slider mechanism operable to adjust the position of thesecond stud at various positions along a slot of the slider mechanism.The tail wheel transporter, where the slider mechanism includes: theslot along at least a portion of a centerline-proximal side of thelifting foot; an axial channel within the lifting foot; a slider blockoperable to slide within the axial channel, where the slider blockincludes: a first threaded bore alignable to the slot and operable toreceive a threaded end of the second stud; and a second threaded borealignable to the slot and operable to receive a set screw. The tailwheel transporter, where the tail wheel transporter is configured toreceive the force of a wheel to be transported on the first and secondstuds of the lifting foot at a vertical position below the rear axlewhen the lifting foot is in a lifted position. The tail wheeltransporter, where the four bar mechanism includes a parallelogramconfiguration. The tail wheel transporter, where the tricycle carriageincludes a bifurcated front wheel. The tail wheel transporter, where thelifting arm includes first and second releasable and re-connectablesections. The tail wheel transporter, where the towing arm includesfirst and second releasable and re-connectable sections.

A tail wheel transporter including: a tricycle carriage furtherincluding a main frame extending off-centered from a rear axle to afront caster attachment plate and a bifurcated front wheel; a pivot barpivotably mounted to a side of the main frame proximate a centerlineorthogonal to the rear axle; a lifting foot pivotably coupled to thepivot bar and extending horizontally, when in a quiescent state, fromthe pivot bar to a point behind the front caster attachment plate, wherethe main frame, the lifting foot, and the pivot bar comprise three barsof a four bar mechanism; a lifting arm extending from the pivot bar; atowing arm extending from the main beam; a latch operable to releasablycouple the lifting arm to the towing arm when the lifting arm is in alifted position; the lifting foot including a first stud extendingsideways across the centerline from the lifting foot; the lifting footincluding a second stud extending sideways from the lifting foot acrossthe centerline and having an adjustable position on the lifting foot;and where the tail wheel transporter is configured to receive the forceof a wheel to be transported on the first and second studs of thelifting foot at a vertical position below the rear axle when the liftingfoot is in a lifted position. The tail wheel transporter, where theadjustable position includes a plurality of threaded bores in thelifting foot, where each bore of the plurality of threaded bores isoperable to receive a threaded end of the second stud; and/or a slidermechanism operable to adjust the position of the second stud at variouspositions along a slot of the slider mechanism. The tail wheeltransporter, where the slider mechanism includes: the slot along atleast a portion of a centerline-proximal side of the lifting foot; anaxial channel within the lifting foot; a slider block operable to slidewithin the axial channel, where the slider block includes: a firstthreaded bore alignable to the slot and operable to receive a threadedend of the second stud; and a second threaded bore alignable to the slotand operable to receive a set screw. The tail wheel transporter, wherethe four bar mechanism further includes a fourth bar pivotably coupledat a first end to the main frame and pivotably coupled at a second endto a front end of the lifting foot.

A tail wheel transporter including: a tricycle carriage furtherincluding a main frame extending off-centered from a rear axle to afront caster attachment plate; a pivot bar pivotably mounted to a sideof the main frame proximate a centerline orthogonal to the rear axle; alifting foot pivotably coupled to the pivot bar as two bars of afour-bar mechanism; a biasing mechanism operable to bias the liftingfoot toward a non-lifted position; a lifting arm extending from thepivot bar; a towing arm extending from the main beam; a latch operableto releasably couple the lifting arm to the towing arm when the liftingarm is in a lifted position; where the lifting foot includes a firststud extending sideways from the lifting foot across the centerline;where the lifting foot further includes a second stud extending sidewaysfrom the lifting foot across the centerline and having an adjustableposition on the lifting foot; and where the tail wheel transporter isconfigured to receive the force of a wheel to be transported on thefirst and second studs of the lifting foot at a vertical position belowthe rear axle when the lifting foot is in a lifted position. The tailwheel transporter, where the adjustable position includes a plurality ofthreaded bores in the lifting foot, where each bore of the plurality ofthreaded bores is operable to receive a threaded end of the second stud;and/or a slider mechanism operable to adjust the position of the secondstud at various positions along a slot of the slider mechanism; wherethe slider mechanism includes: the slot along at least a portion of acenterline-proximal side of the lifting foot; an axial channel withinthe lifting foot; a slider block operable to slide within the axialchannel, where the slider block includes: a first threaded borealignable to the slot and operable to receive a threaded end of thesecond stud; and a second threaded bore alignable to the slot andoperable to receive a set screw. The tail wheel transporter, where thetricycle carriage includes a bifurcated front wheel.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the present invention willbecome more apparent from the following description taken in conjunctionwith the following drawings in which:

FIG. 1 is a side elevation view illustrating an exemplary tail wheeltransporter, according to a preferred embodiment of the presentinvention;

FIG. 2 is a front-left perspective view illustrating the exemplary tailwheel transporter, according to the preferred embodiment of FIG. 1;

FIG. 3 is a rear-left perspective view illustrating the exemplary tailwheel transporter, according to the preferred embodiment of FIG. 1;

FIG. 4 is a top-left-rear perspective view illustrating the exemplarytail wheel transporter, according to the preferred embodiment of FIG. 1;

FIG. 5 is a front-right perspective view illustrating the exemplary tailwheel transporter, according to the preferred embodiment of FIG. 1;

FIG. 6 is a top plan view illustrating the exemplary tail wheeltransporter, according to the preferred embodiment of FIG. 1;

FIG. 7 is a front elevation view illustrating the exemplary tail wheeltransporter, according to the preferred embodiment of FIG. 1;

FIG. 8 is rear elevation view illustrating the exemplary tail wheeltransporter, according to the preferred embodiment of FIG. 1;

FIG. 9 is a left-side elevation view illustrating the exemplary tailwheel transporter, according to the preferred embodiment of FIG. 1;

FIG. 10 is a front-left perspective view illustrating an exemplary tailwheel transporter, according to a second preferred embodiment of thepresent invention;

FIG. 11 is a front-right perspective view illustrating an exemplary anadjustable stud for an exemplary tail wheel transporter, according to asecond preferred embodiment of the present invention as shown in FIG.10;

FIG. 12 is a rear-right perspective view illustrating an exemplary anadjustable stud for an exemplary tail wheel transporter, according to asecond preferred embodiment of the present invention as shown in FIG.10;

FIG. 13 is a side elevation view illustrating an additional exemplarystud support with an adjustable stud for an exemplary tail wheeltransporter, according to a preferred embodiment of the presentinvention;

FIG. 14 is a side elevation view illustrating an additional exemplaryembodiment of a tail wheel transporter, according to a preferredembodiment of the present invention;

FIG. 15 is a front-left perspective view illustrating the exemplaryembodiment for the exemplary tail wheel transporter of FIG. 14,according to a second preferred embodiment of the present invention;

FIG. 16 is a side elevation view illustrating an additional exemplaryembodiment of a tail wheel transporter, according to a preferredembodiment of the present invention; and

FIG. 17 is a front-left perspective view illustrating the exemplaryembodiment for the exemplary tail wheel transporter of FIG. 16,according to a second preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE BEST MODES AND PREFERRED EMBODIMENTS OF THEINVENTION

FIG. 1 is a side elevation view illustrating an exemplary tail wheeltransporter 100, according to a preferred embodiment of the presentinvention. Main frame 102 includes horizontal frame member 104 andangled frame extension 106. Horizontal frame member 104 supportselongated handle 146, axle 202 (see FIG. 2), and pivot 132. Angled frameextension 106 supports caster attachment plate 108. Main frame 102 ispreferably made of substantially rigid material, such as steel oraluminum. In various embodiments, various other materials may be used.For example, in an embodiment where weight is at a premium, such as atail wheel transporter 100 designed to be transported in an aircraft,Boron-epoxy composite may be used. Those of skill in the art,illuminated by the present disclosure, will be aware of materials thatare appropriate for various unique applications.

Caster attachment plate 108 is preferably welded to angled extension106. In an alternate embodiment, main frame 102 and caster attachmentplate 108 may be formed as a single piece. Caster 118 includes casterbase plate 112, caster support arms 114 (one of two shown) and casterwheel 116. Caster 118 may be a commercial-off-the-shelf (COTS) productor may be specially made. Caster base plate 112 is releasably attachedto caster support plate 108, illustrated here as using bolts 110 (one offour labeled, two visible). In various other embodiments, other means ofattachment, such as clamps or various fasteners, may be used. In analternate embodiment, caster base plate 112 may be permanently fixed tocaster support plate 108. Caster wheel 116 and caster support arms 114are free to swivel together about an axis through the caster base plate112. In various other embodiments, various types of casters may be used.

Elongated handle 146 is made of substantially rigid material, and ispreferably welded to horizontal frame member 104. In an alternateembodiment, elongated handle 146 may be releasably attached tohorizontal frame member 104. In yet another alternate embodiment,elongated handle 146 may be made of a composite material. Elongatedhandle 146 supports latch 148, crossbar 210 (See FIG. 2), and handles150 and 250 (See FIG. 2). Latch 148 is rotatable to latch lifting arm138 when lifting arm 138 is moved proximate elongated handle 146. Latch148 is preferably made of metal but may be made of plastic in analternate embodiment. Handles 150 and 250 improve the operator's grip onthe crossbar 210 on the elongated handle 146. Handles 150 and 250 may beCOTS bicycle hand grips, for example. Elongated handle 146 may be madein releasable and re-connectable sections 1044 and 1046 (See FIG. 10)for a portable embodiment.

Rear wheels 144 and 244 (See FIG. 2) preferably include pneumatic tiresand rotate with or on axle 202. Materials for rear wheels 144 and 244may vary, depending on the application for various embodiments. Forexample, a studded tire may be useful for Arctic applications, while atire with high heat resistance may be desired for Arizona tarmacs. Thoseof skill in the art, illuminated by the present disclosure, will beaware of tire material requirements for various operationalenvironments. The diameter of rear wheels 144 and 244 and the verticalextent of caster 118 are selected to maintain horizontal frame member104 in a substantially horizontal orientation and to provide groundclearance to lifting foot 120. Preferably, when the lifting foot 120 isin the lifted position, the point at which the force exerted by theweight on the tail wheel 902 is below axle 202. More preferably, whenthe lifting foot 120 is in the lifted position, the point at which theforce exerted by the weight on the tail wheel 902 is below axle 202 andbelow caster axle 160. Rear wheels 144 and 244, as well as caster 118,axle 202, caster support plate 108, and the main frame 102, form atricycle carriage.

Lifting foot 120 includes stud support 122 rigidly attached to pivot bar134. Preferably, stud support 122 and pivot bar 134 are made as onepiece. Preferably, stud support 122 has an axial channel 123 (See FIGS.11-13). Stud support 122 supports stud 124, stud 128, attachment meansfor spring 136, holes 125 and 126 for a moveable stud 227 (See FIG. 2).Holes 125 and 126 are preferably threaded bores 125 and 126, themoveable stud 227 preferably has an end with complimentary threads tothreaded bores 125 and 126. In alternate embodiments, other means forreleasably attaching moveable stud 227 may be used. The studs 124 and128 engage the aircraft tail wheel 902 (see FIG. 9) from the side andexert force on the tail wheel 902 when the tail wheel 902 is lifted. Theholes 125 and 126 allow the moveable stud 227 to be placed to adjust fortail wheel 902 (See FIG. 9) size. Tire cradle 130 is rigidly attached tofixed stud 128 and operates to prevent the tail wheel 902 from rollingoff the back of fixed stud 128. Tire cradle 130 may be of any shape andsize operable to prevent the tail wheel 902 from rolling off the back offixed stud 128.

Pivot bar 134 receives and rotates upon pivot 132, responsive tomovement of lifting arm 138. Lifting arm 138 includes lifting beam 140and handle 142. Beam 140 makes a 10° angle α with pivot bar 134, andhandle 142 makes a 5° angle β with beam 140, as shown. The length ofbeam 140 and handle 142, as well as the placement of latch 148, arecoordinated such that handle 142 may be latched in the lifted position.Angles α and β depend, in part, on the angle that elongated handle 146makes with horizontal frame member 104 and the distance between thepoint of attachment of elongated handle 146 to horizontal frame member104 and the pivot 132. In various additional embodiments, the angles αand β may vary with such factors, and α and/or β may be zero in someembodiments.

The tail wheel transporter 100 is shown in its quiescent state, as it isprior to lifting a tail wheel 902. In operation, a tail wheel 902 isengaged from the side on studs 124 and 128, or perhaps a moveable stud227, and lifting arm 138 is manually pulled toward the elongated handle146 and latched to elongated handle 146 using latch 148. The load isthus received between the front caster 118 and the rear wheel 144, andno additional manual force is required to maintain lift or balance whilemoving aircraft 900 (see FIG. 9).

FIG. 2 is a front-left perspective view illustrating the exemplary tailwheel transporter 100, according to the preferred embodiment of FIG. 1.Tail wheel transporter 100 is shown in its quiescent state. Axle 202supports axle attachment 204 for spring 136, rear wheel 144, rear wheel244, and main frame 102. Spring 136 biases the pivot bar 134, liftingfoot 120, and lifting arm 138 towards the quiescent state, as shown.Moveable stud 227 is shown in position to assist with a lift. Latchpivot 208 is shown and latch 148 may be more clearly understood fromthis illustration. Elongated handle 146 terminates in a cross bar 210that supports handles 150 and 250. Support flange 206 supports elongatedhandle 146 relative to horizontal frame member 104. The offset of mainframe 102 on axle 202 may be more clearly understood by reference toFIG. 2. Note that both the main frame 102 and the lifting foot 120 areoffset from the center of axle 202.

FIG. 3 is a rear-left perspective view illustrating the exemplary tailwheel transporter 100, according to the preferred embodiment of FIG. 1.The tail wheel transporter 100 is shown in its lifted state, withlifting arm 138 rotated back to elongated handle 146 and latched toelongated handle 146 by the manual pivoting of latch 148 about latchpivot 208. Lifting foot 120 is raised by the lever action of liftinghandle 138 and pivot bar 134. Lifting arm stop 302 is illustrated as aflange attached to main frame 102 and a bolt through a threaded bore inthe flange that can be turned to adjust the point at which thespring-biased downward travel of the lifting arm 138 stops. Bore 304,preferably a threaded bore, is for storage of moveable stud 227 when itis not in use.

FIG. 4 is a top-left-rear perspective view illustrating the exemplarytail wheel transporter 100, according to the preferred embodiment ofFIG. 1. The tail wheel transporter 100 is shown in its quiescent state.The pivot arm 134 is in contact with the lifting arm stop 302.

FIG. 5 is a front-right perspective view illustrating the exemplary tailwheel transporter 100, according to the preferred embodiment of FIG. 1.The tail wheel transporter 100 is shown in its quiescent state.

FIG. 6 is a top plan view illustrating the exemplary tail wheeltransporter 100, according to the preferred embodiment of FIG. 1. Thetail wheel transporter 100 is shown in its quiescent state. This viewemphasizes that both the main frame 102 with elongated handle 146 andlifting foot 120, pivot bar 134, and lifting handle 138 are offset fromthe centerline 602 of axle 202. Studs 124, 227, and 128, as well as tirecradle 130 all extend through the centerline 602, meaning that theweight exerted by the tail wheel 902 is approximately centeredside-to-side.

FIG. 7 is a front elevation view illustrating the exemplary tail wheeltransporter 100, according to the preferred embodiment of FIG. 1. Thetail wheel transporter 100 is shown in its quiescent state.

FIG. 8 is rear elevation view illustrating the exemplary tail wheeltransporter 100, according to the preferred embodiment of FIG. 1. Thetail wheel transporter 100 is shown in its quiescent state.

FIG. 9 is a left-side elevation view illustrating the exemplary tailwheel transporter 100, according to the preferred embodiment of FIG. 1.The tail wheel transporter 100 is shown in its lifted state, with tailwheel 902 of aircraft 900 supported by fixed stud 128 and moveable stud227. Latch 148 is latched, and the load is received between front andrear axles, making the lifted state a stable state.

Those of skill in the art, illuminated by the present disclosure, willappreciate that, while the example provided operates manually, theinvention may also be implemented mechanically or hydraulically bymerely replacing the manual force on the lifting arm 138 with amechanical or hydraulic force. The force may be powered by electrical orother means. Likewise, embodiments made lightweight and more portable ormore easily shippable are also within the scope of the presentinvention. Various embodiments of the invention may be equipped with amotorized system to propel the tail wheel transporter 100.

FIG. 10 is a front-left perspective view illustrating an exemplary tailwheel transporter 1000, according to a second preferred embodiment ofthe present invention. Tail wheel transporter 1000 has a lifting arm1038 for which the angles α and β are zero. Lifting arm 1038 has firstand second releasable and re-connectable sections 1042 and 1044releasably joined with a telescoping rod and pin assembly 1050, allowingfor disassembly for shipping. Towing arm 1040 has first and secondreleasable and re-connectable towing arm sections 1046 and 1048releasably joined with a telescoping rod and pin assembly 1052, allowingfor disassembly for shipping. Towing arm section 1048 is releasablyaffixed to main frame end member 1066, preferably in alignment withhorizontal frame member 1004. Rear axle 202 extends through main frame1004. Main frame 1002 includes horizontal frame member 1004 and angledframe extension 106. Horizontal frame member 1004 supports releasablyattachable plate 1066 which is welded to the bottom end of secondsection 1048 of towing arm 1040 and bolted to main frame 1004.

Lifting foot 1020 includes stud support 1022 rigidly attached to pivotbar 134. Preferably, stud support 1022 and pivot bar 134 are made as onepiece. Stud support 1022 includes stud 128, a slot 1028 from whichprotrudes stud 1027, a slider mechanism 1100 (See FIG. 11), andattachment means for spring 136. Attachment means for spring 136 may bea loop or other coupling for receiving or engaging and end portion ofspring 136. The moveable stud 1027 preferably has an end withcomplimentary threads to the threaded bore 1106 (see FIG. 11) in theslider mechanism.

Surfaces 1029 and 1032 are preferably high-friction surfaces. Forexample, surfaces 1029 and 1032 may be covered with SAFETY-WALK™adhesive tread made by the 3M Company of St. Paul, Minn.

FIG. 11 is a front-right perspective view illustrating an exemplaryadjustable stud 1027 for an exemplary tail wheel transporter 1000,according to a second preferred embodiment of the present invention asshown in FIG. 10. Stud support 1022 is hollow and has a slot 1028 on oneside through which stud 1027 protrudes. Slider block 1102 movesslidingly within hollow stud support 1022. Slider block 1102 has a firstthreaded bore 1106 into which complimentary threads at a first end ofstud 1027 are threaded. A second end of stud 1027 has a driver receiver1108 (illustrated as a screwdriver slot) for tightening stud 1027 inplace. Slider block 1102 has a second threaded bore 1104 into whichcomplimentary threads of a set screw 1110 are threaded. Set screw 1110is preferably an Allen-head screw, but other driver receivers 1112,including unique driver receivers 1112, are within the scope of theinvention. The slider mechanism 1100 includes the slot 1028, sliderblock 1102, set screw 1110, and stud 1027. Slider mechanism 1100 permitsadjustment to any size tail wheel 902, and is not limited toaccommodating discrete popular sizes. An Allen wrench or similar drivermay be provided by the consumer or, in an alternate embodiment, may besupplied with tail wheel transporter 1000.

FIG. 12 is a rear-right perspective view illustrating an exemplaryadjustable stud 1027 for an exemplary tail wheel transporter 1000,according to a second preferred embodiment of the present invention asshown in FIG. 10. Slider block 1102 is shown from the rear with thethreads of stud 1027 protruding through the slider block 1102 and setscrew 1110 also protruding through slider block 1102. Thisconfiguration, when achieved inside hollow stud support 1022, locks thestud 1027 and slider block 1102 from sliding within the hollow studsupport 1022. Slider mechanism 1100 allows locking in various analogpositions along the slot 1028 to accommodate tail wheels 902 of a widerange of sizes.

FIG. 13 is a side elevation view illustrating an alternate exemplarystud support 1322 with an adjustable stud 1027 for an exemplary tailwheel transporter, according to a preferred embodiment of the presentinvention. Stud support 1322 differs from stud support 1022 of FIG. 10in that the outside corners 1306 (one of two labeled) and the insidecorners 1304 (one of two labeled) of the stud support 1322 are rounded,whereas the stud support 1022 illustrated in FIG. 10 does not haverounded corners. The difference illustrates that, in various alternateembodiments, various internal and external cross-sectional shapes may beused for stud support 1322. Slider block 1302 is shown inside hollowstud support 1322 in the fully tightened position and is engaged by thethreads of adjustable stud 1027 to assist in locking the slider block1302 in place Slider block 1302 has conformally shaped corners 1308 (oneof two labeled) that are received by inside rounded corners 1304 of studsupport 1322. In various alternate embodiments, slider block 1302 has ashape at least partially conformal to the inside cross-sectional shapeof the stud support 1322.

FIG. 14 is a side elevation view illustrating an additional exemplaryembodiment of a tail wheel transporter 1400, according to anotherpreferred embodiment of the present invention. Tail wheel transporter1400 is similar to tail wheel transporter 100 except tail wheeltransporter 1400 uses a four-bar mechanism 104, 1434, 1422, and 1450 toimplement lifting foot 1420. Pivot 1404 pivotably couples frame member104 to a top end of free bar 1450. The bottom end of free bar 1450 ispivotably coupled (not visible in this view) to the forward end of studsupport 1422. The rear end of stud support 1422 is pivotably coupled topivot bar 1434 by pivot 1430. Pivot bar 1434 is pivotably coupled bypivot 132 to frame member 104, thereby completing the four-barmechanism. When handle 142 is moved to rotate pivot bar about pivot 132,stud support 1422 moves upward with little or no tilting. Stud support1422 supports one moveable stud 1424 that can be releasably fixed withinslot 1426, as described in detail in regard to FIGS. 11-13, and onefixed stud 1428 that also serves as an axle for pivot 1430. Spring 136attaches to the rear end of stud support 1422. In operation, a tailwheel 1402 rests on studs 1424 and 1428, is lifted or lowered by actionof handle 142, and may be transported, along with the vehicle it isconnected to, by manual operation of elongated handle 146. The remainingportions for tail wheel transporter 1400 are the same as tail wheeltransporter 100.

FIG. 15 is a front-left perspective view illustrating the exemplaryembodiment for the exemplary tail wheel transporter 1400 of FIG. 14,according to another preferred embodiment of the present invention.Spacers 1452 may be used between frame member 104 and pivot bar 1434 toprovide space for free bar 1450. Fixed stud 1428 can be more clearlyseen as the axle of pivot 1430. Variations in the relative lengths ofthe four bar mechanism are within the scope of the invention. While theexemplary embodiments are manually operated, motorized embodiments arealso within the scope of the invention.

FIG. 16 is a side elevation view illustrating an additional exemplaryembodiment of a tail wheel transporter 1600, according to a preferredembodiment of the present invention. Tail wheel transporter 1600features the four bar mechanism 1604, 1450, 1422, and 1434 as tail wheeltransporter 1400, but differs in having a low-profile front end 1602.Low-profile front end 1602 includes a caster support plate 1608 fixed(preferably welded) to the top surface of frame member 1604 proximatethe front end of the frame member 1604. Caster support plate 1608supports two casters 1618 (one visible in this view) each having a wheel1616 and a pair (one visible in this view) of wheel support arms 1614that are rotationally coupled to a caster mounting plate 1612. Thecaster mounting plate 1612 is releasably fixed to the caster supportplate 1608 with fasteners 1610, illustrated as bolts 1610 (one of twolabeled). Frame member 1604 is illustrated as straight, but theinvention is not so limited. Caster support plate 1608 is illustrated asflat, but the invention is not so limited. The advantage of the lowprofile front end 1602 is that it allows the tail wheel transporter 1600to be used in situations where there is low clearance under the aircraftor other vehicle. Using dual casters 1618 spreads the load, allowingsmaller casters 1618 to be used.

FIG. 17 is a front-left perspective view illustrating the exemplaryembodiment for the exemplary tail wheel transporter 1600 of FIG. 16,according to a second preferred embodiment of the present invention. Alleight bolts 1610 (one of eight labeled) can be more clearly seen, alongwith dual casters 1618. The illustrated shape of caster support plate1608 is not a limitation of the invention. Tail wheel transporter 1600still uses a tricycle carriage but has bifurcated front wheels 1618.

While at least one exemplary embodiment has been presented in theforegoing detailed description, it should be appreciated that a vastnumber of variations exist. It should also be appreciated that theexemplary embodiment or exemplary embodiments are only examples, and arenot intended to limit the scope, applicability, or configuration of theinvention in any way. For example, and embodiment in which the rearwheels are casters and the front wheel is fixed is contemplated. Rather,the foregoing detailed description will provide those skilled in the artwith a convenient road map for implementing the exemplary embodiment orexemplary embodiments. It should be understood that various changes canbe made in the function and arrangement of elements without departingfrom the scope of the invention as set forth in the appended claims andthe legal equivalents thereof.

I claim:
 1. A tail wheel transporter comprising: a. a tricycle carriage further comprising a main frame extending off-centered from a rear axle to a front caster attachment plate; b. a pivot bar pivotably mounted to a side of said main frame proximate a centerline orthogonal to said rear axle; c. a lifting foot pivotably coupled to said pivot bar and extending horizontally, when in a quiescent state, from said pivot bar to a point behind said front caster attachment plate, wherein said main frame, said pivot bar, and said lifting foot are three bars of a four bar mechanism; d. a lifting arm extending from said pivot bar; e. a towing arm extending from said main frame; and f. a latch operable to releasably couple said lifting arm to said towing arm when said lifting arm is in a lifted position.
 2. The tail wheel transporter of claim 1, further comprising a biasing mechanism operable to bias said lifting foot toward a non-lifted position.
 3. The tail wheel transporter of claim 1, further comprising a fourth bar of said four bar mechanism pivotably coupled on first and second ends to said main frame and said lifting foot, respectively.
 4. The tail wheel transporter of claim 1, wherein said lifting foot further comprises a first stud extending sideways from said lifting foot across said centerline.
 5. The tail wheel transporter of claim 4, wherein said first stud further comprises an axle for one pivotable coupling of said four bar mechanism.
 6. The tail wheel transporter of claim 5, where the lifting foot further comprises a second stud extending sideways from said lifting foot across said centerline and having an adjustable position on said lifting foot.
 7. The tail wheel transporter of claim 6, wherein said adjustable position comprises a slider mechanism operable to adjust the position of said second stud at various positions along a slot of said slider mechanism.
 8. The tail wheel transporter of claim 7, wherein said slider mechanism comprises: a. said slot along at least a portion of a centerline-proximal side of said lifting foot; b. an axial channel within said lifting foot; c. a slider block operable to slide within said axial channel, wherein said slider block comprises: i. a first threaded bore alignable to said slot and operable to receive a threaded end of said second stud; and ii. a second threaded bore alignable to said slot and operable to receive a set screw.
 9. The tail wheel transporter of claim 6, wherein said tail wheel transporter is configured to receive the force of a wheel to be transported on said first and second studs of said lifting foot at a vertical position below said rear axle when said lifting foot is in a lifted position.
 10. The tail wheel transporter of claim 1, wherein said four bar mechanism comprises a parallelogram configuration.
 11. The tail wheel transporter of claim 1, wherein said carriage comprises a bifurcated front wheel.
 12. The tail wheel transporter of claim 1, wherein said lifting arm comprises first and second releasable and re-connectable sections.
 13. The tail wheel transporter of claim 12, wherein said towing arm comprises first and second releasable and re-connectable sections.
 14. The tail wheel transporter of claim 1, wherein said four bar mechanism further comprises a fourth bar pivotably coupled at a first end to said main frame and pivotably coupled at a second end to a front end of said lifting foot.
 15. A tail wheel transporter comprising: a. a carriage further comprising a main frame extending off-centered from a rear axle to a front caster attachment plate and a bifurcated front wheel; b. a pivot bar pivotably mounted to a side of said main frame proximate a centerline orthogonal to said rear axle; c. a lifting foot pivotably coupled to said pivot bar and extending horizontally, when in a quiescent state, from said pivot bar to a point behind said front caster attachment plate, wherein said main frame, said lifting foot, and said pivot bar comprise three bars of a four bar mechanism; d. a lifting arm extending from said pivot bar; e. a towing arm extending from said main frame; f. a latch operable to releasably couple said lifting arm to said towing arm when said lifting arm is in a lifted position; g. said lifting foot comprising a first stud extending sideways across said centerline from said lifting foot; h. said lifting foot comprising a second stud extending sideways from said lifting foot across said centerline and having an adjustable position on said lifting foot; and i. wherein said tail wheel transporter is configured to receive the force of a wheel to be transported on said first and second studs of said lifting foot at a vertical position below said rear axle when said lifting foot is in a lifted position.
 16. The tail wheel transporter of claim 15, wherein said adjustable position comprises at least one of: a. a plurality of threaded bores in said lifting foot, wherein each bore of said plurality of threaded bores is operable to receive a threaded end of said second stud; and b. a slider mechanism operable to adjust the position of said second stud at various positions along a slot of said slider mechanism.
 17. The tail wheel transporter of claim 16, wherein said slider mechanism comprises: a. said slot along at least a portion of a centerline-proximal side of said lifting foot; b. an axial channel within said lifting foot; c. a slider block operable to slide within said axial channel, wherein said slider block comprises: i. a first threaded bore alignable to said slot and operable to receive a threaded end of said second stud; and ii. a second threaded bore alignable to said slot and operable to receive a set screw.
 18. A tail wheel transporter comprising: a. a tricycle carriage further comprising a main frame extending off-centered from a rear axle to a front caster attachment plate; b. a pivot bar pivotably mounted to a side of said main frame proximate a centerline orthogonal to said rear axle; c. a lifting foot pivotably coupled to said pivot bar as two bars of a four-bar mechanism; d. a biasing mechanism operable to bias said lifting foot toward a non-lifted position; e. a lifting arm extending from said pivot bar; f. a towing arm extending from said main frame; g. a latch operable to releasably couple said lifting arm to said towing arm when said lifting arm is in a lifted position; h. wherein said lifting foot comprises a first stud extending sideways from said lifting foot across said centerline; i. wherein said lifting foot further comprises a second stud extending sideways from said lifting foot across said centerline and having an adjustable position on said lifting foot; and j. wherein said tail wheel transporter is configured to receive the force of a wheel to be transported on said lifting foot at a vertical position below said rear axle when said lifting foot is in a lifted position.
 19. The tail wheel transporter of claim 18, wherein said adjustable position comprises at least one of: a. a plurality of threaded bores in said lifting foot, wherein each bore of said plurality of threaded bores is operable to receive a threaded end of said second stud; and b. a slider mechanism operable to adjust the position of said second stud at various positions along a slot of said slider mechanism; c. wherein said slider mechanism comprises: i. said slot along at least a portion of a centerline-proximal side of said lifting foot; ii. an axial channel within said lifting foot; iii. a slider block operable to slide within said axial channel, wherein said slider block comprises:
 1. a first threaded bore alignable to said slot and operable to receive a threaded end of said second stud; and
 2. a second threaded bore alignable to said slot and operable to receive a set screw.
 20. The tail wheel transporter of claim 18, wherein said carriage comprises a bifurcated front wheel. 